Motor vehicle headliners have been mounted to the body structure of a vehicle in a series of individual steps on a vehicle assembly line. Several steps are involved in installing a headliner substrate and various accessory components to the substrate, and to the vehicle, to hold the substrate in position. This type of assembly requires numerous assembly stations and numerous assembly operators to complete.
The herein invention is concerned with a modular headliner which is assembled as a unitary element to a motor vehicle at a single assembly station. Additionally the herein described modular headliner is designed to be assembled to the vehicle body and specifically to the vehicle body structure by being snap-fit to the vehicle body structure such that the operator need not enter the vehicle to mount the modular headliner thereto.
A portion of the modular headliner is secured to the vehicle body structure by an assist strap preferably positioned along the side of the modular headliner towards the rear and positioned such that upon assembly the headliner to the vehicle the assist strap will be in a position such that the user or occupant of the vehicle as they enter or leave through the vehicle door may use the assist strap act as a grab handle for providing assistance as they enter or exit through the door or under adverse driving conditions.
The assist strap as described herein includes a base and at least one set of projecting legs which extend through the substrate and through an opening in the vehicle body structure to engage the vehicle body structure on the opposite side such that the substrate and vehicle body structure are secured between the legs and the base of the assist strap. In most assist straps at least two sets of legs will be utilized to promote further securing of the assist strap and the attached headliner to the vehicle body structure. Additional sets of projecting legs may be used as appropriate.
The assist strap acts to lock the headliner to the vehicle body structure by the provision of a mandrel having a first position which allows the projecting legs of the assist strap to be flexed such that the legs may be compressed together for insertion through the opening of the vehicle body structure and a second position wherein the mandrel is placed between the legs such that the legs may not be compressed thereby locking the legs with a portion of the legs extending behind the vehicle body structure to engage the opposite side of the vehicle body structure from the substrate to sandwich the substrate between the vehicle body structure and the assist strap base. In this manner the legs of the assist strap are locked to the vehicle body structure and the headliner is mounted in position.
To make the assembly of the modular headliner to the vehicle body structure even easier the assist strap is designed to have a pivotally mounted handle positioned, such that upon the application of force to the handle, the handle will be displaced driving the mandrel from the first position to the second position. The handle includes a smooth surface such that there is very little friction between the handle and the mandrel as it is driven from first position to second position and the handle is appropriately arranged such that upon pivotal displacement of the handle, the force is applied in a direction parallel to the axis of the mandrel to drive the mandrel in an axial sliding motion as opposed to applying a twisting force thereto.
In order to assure that sufficient force is applied to the handle to drive the mandrel from the first position to the second position a breakaway tab is utilized to secure the handle in a preassembled position. A spring biases the handle to an upright position, however the handle is maintained in a fixed position by breakaway tab prior to assembly. The breakaway tab is sized such that upon the application of sufficient force to break the tab, the force will be sufficient to drive the mandrel from the first position to the second position. The size of the breakaway tab is selected to tune the force such that the minimum force required to break the tab is sufficient to drive the mandrel completely to the second position.
The assist strap for use with the modular headliner further includes a retainer clip for engaging the fastening means of the assist strap and potentially other portions of the assist strap on the side of the substrate opposite from the base of the assist strap such that the substrate is secured therebetween and the assist strap is mounted to the substrate prior to the modular headliner being mounted to the vehicle body structure. In this manner the assist strap is maintained in position as a portion of the modular headliner prior to the assembly of the modular headliner to the vehicle body structure.
The use of an assist strap having a "smack set handle" as described herein allows the installer to simply smack the handle to drive the mandrel to the home position and is compatible with the entire assembly of the modular headliner to the motor vehicle with snap-in fasteners. As the installer is fastening the modular headliner to the vehicle the installer will feel the fastening means pass through the vehicle body structure opening when the legs then snap outwardly. Once he feels this engagement he knows that upon smacking the assist strap handle with his hand, he will, if the smack is of sufficient force to rupture the breakaway tab, cause the handle to engage the mandrel and drive the mandrel from the first position to the second position to lock the assist strap and consequently the headliner to the vehicle body structure.
The mandrel is sized to extend from the assist strap base outwardly towards the handle in the preassembled position. The mandrel includes a larger diameter head and a smaller diameter base. The assist strap base defines a larger diameter opening for receipt of the mandrel head and a smaller diameter opening extending therethrough through which the base of the mandrel may pass. Upon the mandrel being displaced to the second position, the head of the mandrel is contained within the larger opening in the assist strap base such that assist strap base presents a pleasing final appearance to observers within the vehicle.
The method of mounting the assist strap and retainer for securing the assist strap to the headliner prior to assembly of the headliner to the vehicle body may be utilized with other accessories. The other accessories may include items as part of modular headliner such as a coat hook, coat hanger, storage module, light module, console, display, sunshade support and the like.